A question about online trading.
I run an online shop and can offer various payment methods to my customers. One of these payment methods is Klarna. The principle is as follows:
A customer wants to order a product and transfer the money for it. A transfer would normally take several days. However, if he pays with Klarna, I will receive the money from Klarna immediately, and the customer can pay Klarna within 14 days. Klarna is an advantage because it also guarantees absolute cyber and legal security for me as a dealer. There are no fees for the customer. However, I pay a small transaction fee per sale, which is set in advance.
Is it allowed for me to offer my customers this payment method?
بِسْمِ اللهِ الرَّحْمنِ الرَّحِيْم
In the name of Allah, the Most Gracious, the Most Merciful
As the seller, you have the right to seek payment from the buyer of the product or the one who is a guarantor for him, so this is permissible.
Only Allah knows best
Written by Maulana Moinul Abu Hamza
Checked and approved by Mufti Mohammed Tosir Miah
Darul Ifta Birmingham
 Mukharasar al-Qudoori, Tahir Kiani Translation, Page 298 and 300